1x [string "*BigDebuffs.xml:23_OnEnter"]:3: Invalid spell ID in GameTooltip:SetSpellByID
[string "=[C]"]: in function `SetSpellByID'
[string "*BigDebuffs.xml:23_OnEnter"]:3: in function <[string "*BigDebuffs.xml:23_OnEnter"]:1>

This happens because this line adds an entry to the debuffs table that includes a boolean where an integer (spell ID) is expected.

The true should be changed to warningId